The present invention relates to a method and apparatus for the stacking and loading of filled egg cartons.
Presently, egg cartons filled with eggs are stacked and loaded into carts manually. The fragility of egg cartons, now typically made of foamed plastic material, and of the eggs they contain, create unique handling problems which have prevented the development of a practical egg carton stacking and loading device. One problem encountered in the stacking of fragile objects, such as egg cartons, is that the dropping of the carton onto the top of a stack may damage the cartons or the eggs in them.
One difficulty associated with the transfer of stacks of relatively small packages, such as egg cartons, is that these relatively small objects do not provide a stable base in the manner provided by larger objects such as lumber and the like. The transfer of stacked egg cartons therefore provides problems not experienced with larger or more stable stacked objects. For example, when a stack that is relatively tall compared to its carton size is slid along a supporting surface, the stack is prone to tipping over.
Although a simple conveyor may be adequate for the transfer of certain stacked objects, other packages would require additional lateral support. For this reason, many carton stacks are shrink wrapped or palletized for transfer. Unfortunately, this would drive up the cost of the eggs, and eggs are already a very competitive commodity.
Such difficulties have posed problems to the egg processing industry in the automation of handling operations for filled egg cartons. To date, a commercially successful automated egg carton stacker and loader has not been developed.